The proper tensioning of lines, cables, ropes, straps and the like has long been a subject of development for many years across many fields. Many techniques have been developed to place lines under tension for a wide variety of applications. Competitive swimming activities often require the installation and deployment of swimming pool lane lines according to internationally recognized standards such as length, width and configuration. Competition and safety standards must often be followed in the installation and maintenance of such lane lines, including attachment methods and height relative to the water's surface. FINA rules require recessed wall anchors for lane lines, floats adjacent thereto be on the surface of the water, and firmly stretched lane lines. Some applications may have tension tolerances.
Prior art swimming line tensioners typically are of two forms. One is a simple ratchet mechanism and the other an encapsulated turnbuckle device. Ratcheting devices generally are known and used to provide means for tensioning straps, cables and the like by winding the line thereby incrementally increasing the tension in the line. One common method known in the art for placing swimming lane lines under tension involves a simple ratchet system comprising a frame structure supporting a rotatable ratcheting reel secured with a locking pawl affixed to the frame. The line is passed through one end of the frame and wound about the reel, while the opposing end of the frame is attached to an anchoring point in the swimming pool. The shaft on which the ratchet reel is fixed includes a means for engaging a tool used to advance the shaft and ratchet reel in the winding direction thereby winding the lane line and increasing the tension therein. The locking pawl secures the reel against the unwinding force. Typically, a soft cover made of padded material is secured about the device to protect swimmers from inadvertent contact with sharp edges on the device.
While these simple devices effectively increase tension in the line, there still exist several disadvantages to the user. For example, the installation and adjustment of these types of devices requires the use of a tool, which can increase the time required for installation and maintenance. Furthermore, such tools can be lost easily and require separate storage. Similarly, the protective covers can be susceptible to damage or can be lost when separated from the device. Additionally, it can be difficult for a user of such devices to achieve the proper tension required for optimal and acceptable lane line deployment. This can lead to problems with improperly tensioned lane lines, severe reductions in the useful life of such lines from fatigue and inelastic stretching due to over-tensioning, or even line failure. This issue has been observed by the Applicant to be a prevalent disadvantage of prior art devices. Therefore, there exists a need in the art for a device that provides for simplified installation and maintenance procedures, as well as an ability to maintain proper tension in the line.
Another common tensioning device found in use in these applications exhibits a turnbuckle-type design, also referred to as stretching screws or bottlescrews. These devices typically comprise an elongated body with a line attachment point at one end, and screw-type turnbuckle elements at the opposite end. The inner portion of these devices provides space for a threaded eye bolt to be threaded in and out of the opposite end from the line by turning the exterior body. While these devices offer a slim profile without the need for a separate protective covering, their application requires that they be quite long relative to the ratchet-type devices. Furthermore, the adjustment process typically demands hand-turning the body of the device many times to achieve proper tension. This can be time consuming and also suffers from the disadvantage of not providing any feedback as to the proper amount of tension in the line, similarly leading to over-tightening issues as discussed above. Further still, turnbuckle devices of this type are significantly limited as to the amount of slack in the line that can be taken up, i.e., in typical applications the length of slack in the line that may be taken up corresponds to half of the length of the threaded eye bolt. Therefore, because the line to be tensioned is not wound up as is common in ratchet-type devices, any natural lengthening due to cable stretching often leads to the need to uninstall the tensioning device, shorten the line and re-install.
During a normal cable lifecycle some natural stretching is typically expected, even under optimal load conditions. None of the known devices provide feedback as to the safety bounds of elongation. Therefore, there exist deficiencies in the art wherein known devices—in addition to not adequately preventing premature elongation—do not assist the user in defining the upper bounds of safe elastic length take-up or indicate to the user that the core cabling should be replaced.
Tensioning devices exist in other applications that operate differently from basic devices employing ratchet or turnbuckle features, but none are known to provide solutions to the disadvantages presently found in the art. For example, Squires (US Pub. No. 2013/0111716) discloses a combination of these principals in a tensioning device designed to increase the tension applied through the device and to prevent theft and tampering with the device. However, the device disclosed therein requires additional drive tools to achieve proper tension and would be more difficult to install and maintain than known devices presently used in the art.
Similarly, Chance (U.S. Pat. No. 6,279,415) discloses a self-tension system ideal for use in automotive actuation cables. However, the device disclosed is difficult to install with heavy-duty cabling and high-tension situations. To provide adequate installation clearance for the associated cables, the length dimension would be too large for the intended application. Furthermore, the device does not provide a means for compensating for extensive slack from extended cable use (e.g., by reeling). The device disclosed in Chance is designed for non-maintenance situations, i.e., so that no adjustments are necessary on the part of the user. This is a purpose counter to the needs described in the swimming lane line field, as swimming lane lines are typically installed and removed for storage from a swimming pool many times, thus consistently requiring user intervention.
Glass (U.S. Pat. No. 8,806,952) discloses a device for measuring tension force on a net cord of a sports net, but is intended for integration with existing line tensioning systems such as those applied to tennis court nets. This use of this device would not overcome the disadvantages of prior art line tensioning systems, however, and further does not provide feedback on proper cable tension (rather, indicating a range of magnitudes only). Furthermore, the configuration of the device is such that the magnitude indicator is situated physically away from the means of providing cable tension, making tension maintenance more cumbersome.
It is therefore an unmet need in the prior art for an adjustable line tensioning device that provides a means for proper tension maintenance without requiring adjustment tools, that has simple installation characteristics, that provides ample adjustment tolerances, and that exhibits desirable size, profile and safety characteristics with regard to competitive standards. No known references, taken alone or in combination, are seen as teaching or suggesting the presently claimed lane line tensioning apparatus.